Behind-the-ear hearings aids in which a sound tube conducts sound generated by the receiver of the hearing aid into the ear canal are well known in the art. In order to position the sound tube securely and comfortably in the ear canal, an earpiece, shell, or earmould is provided for insertion into the ear canal of the user.
Typically, the earpiece, shell, or earmould is individually custom manufactured to fit the user's ear to sufficiently secure the hearing aid tube in place in the ear canal and prevent the earpiece from falling out of the ear and avoid acoustical feed back, e.g., when the user is moving around. The custom made earpiece adds to the cost of the device and the time needed to fit the hearing aid.
In order to lower the manufacturing cost, it is known to manufacture the earpiece, shell, or earmould in a number of standard sizes to fit the human anatomy of the ear of most users.
So-called “open” BTE earpieces are generally preferred in order to affect the ear canal as little as possible by avoiding blockage of the ear canal, i.e. the occlusion effect. This also assists in maintaining the natural hearing capacity and the physical environment of the user.
U.S. Pat. No. 5.753.870 discloses a BTE hearing aid with a connector for connection of a sound tube to an earmould. One end of the connector is adapted for receiving the sound tube and further accommodating a filter for improved sound quality. The bends of the propagation path is provided by the hook of the BTE housing and the connector, respectively. The sound tube is substantially straight in its mounted position.
EP 1 448 014 discloses a BTE hearing aid with an earpiece that is adapted for insertion into an ear canal of a user and has at least one resilient fibre that is connected to the earpiece for abutting a lower part of the concha when the earpiece has been inserted in the ear canal thereby providing retention of the earpiece in the ear canal of the user.
Typically, the sound tube is attached to a connector for coupling of the sound tube to the BTE housing containing the electronics of the hearing aid. The sound tube is typically flexible so that the sound tube is allowed to bend and provide the required arcuate propagation path of the sound from the receiver output at the BTE housing to the earpiece, shell, or earmould. The sound tube is cut in the desired length.
In the BTE hearing aid disclosed in EP 1 448 014, the sound tube has a pre-formed shape that includes a first bend extending from the connector over the top of the ear of the user and a second bend extending from an outside of the ear into an ear canal of the user.
It is also known to manufacture the sound tube with connector and earpiece in one unit in a large variety of standard sizes, for example with different lengths between the first and the second bend, e.g. 4 different lengths, and different lengths between the second bend and the earpiece, e.g. 2 different lengths, to fit the human anatomy of the ear of most users. Further, the sound tubes may be fitted with earpieces of different sizes e.g. 3 different standard sizes, or custom mold. Finally, the sound tube has to be manufactured with bends adapted to the right ear and bends adapted to the left ear. The present example leads to 48 (4*2*3*2) standard sizes of the unit to be manufactured and to be kept in stock by the hearing aid dispensers. Still further, the sound tube may be delivered with various diameters further multiplying the required number of standard sizes.
Further, different manufactures of hearing aids typically apply different coupling principles for coupling of the sound tube connector to the hearing aid housing, such as threading, snap fit coupling, etc, which multiplies the variety of sound tube units to be kept in stock by the hearing aid dispenser.
There is a need for a device that can diminish the number of parts to be kept in stock by hearing aid dispensers.